Active Damping-Based Control for Grid-Connected $LCL$ -Filtered Inverter With Injected Grid Current Feedback Only
Active Damping-Based Control for Grid-Connected $LCL$ -Filtered Inverter With Injected Grid Current Feedback Only
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DOI：
10.1109/tie.2013.2290771
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发表时间：
2014-09
影响因子：
7.7
通讯作者：
Jinming Xu;Shaojun Xie;Ting Tang
中科院分区：
文献类型：
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作者：
Jinming Xu;Shaojun Xie;Ting Tang
LCL型滤波器广泛应用于并网逆变器中。然而，仅采用注入电网电流控制，无法容忍由谐振峰值引起的电流谐波和低带宽。带有额外反馈的主动阻尼（AD）方法提供了对共振的高度抑制，从而改善了动态性；然而，用于额外反馈的高精度传感电路增加了成本。本文利用信号流图和响应拟合方法，提出了一种基于注入电网电流反馈的AD方法。然后，新颖的闭环电流控制仅需要精确地感测注入的电网电流，而不需要观察。与额外的反馈方法相比，降低了成本和复杂性，同时提高了可靠性。基于控制器与系统动力学之间关系的研究，提出了一种简单的设计。对鲁棒性、谐波抑制和数字实现进行了研究。与传统的控制方法相比，所提出的方法在模拟和数字实现上都具有令人满意的性能。仿真和实验验证了所提出的控制和设计策略。
An LCL-type filter is widely used in the grid-connected inverter. However, with only injected grid current control, the current harmonics and low bandwidth caused by the resonance peak cannot be tolerated. The active damping (AD) method with an extra feedback provides a high rejection of the resonance so that the dynamic is improved; however, the high-precision sensing circuit for the extra feedback increases the cost. In this paper, with the signal flow graph and response-fitting methods, an AD method based on the feedback of the injected grid current has been proposed. Then, the novel closed-loop current control requires accurately sensing the injected grid current only, while no observation is needed. Compared with the extra feedback methods, the cost and the complexity are reduced while the reliability is improved. Based on the study of the relation between the controller and the system dynamic, a straightforward design has been proposed. The robustness, harmonic rejection, and digital implementation have been studied. Compared with the conventional control methods, the proposed one promises the satisfactory performance with both analog and digital implementations. Simulations and experiments have verified the proposed control and design strategies.